Implant cutting block pin placement

ABSTRACT

A system, method, and device for drilling holes ( 420, 422 ) in a target bone ( 414 ) are described. For example, the system includes a cutting tool ( 330 ), a navigation system ( 310 ) configured to track a position of the cutting tool, and a computer-assisted surgical (CAS) system ( 340 ) operably connected to the cutting tool and the navigation system. The CAS system can be configured to determine an implant component ( 100 ) to be implanted on the target bone ( 414 ), determine a cutting block position for preparing the target bone to receive the implant component, determine a plurality of pin locations ( 420, 422 ) for securing the cutting block ( 416 ) based upon the determined cutting block position, and selectively provide instructions to the cutting tool to cut a hole when the cutting tool is in a position adjacent to at least one of the determined plurality of pin locations.

CLAIM OF PRIORITY

This application is a continuation of U.S. Patent Application Ser. No.16/066,939, titled “Implant Cutting Block Pin Placement,” filed Jun. 28,2018, which is a U.S. national stage filing under 35 U.S.C. § 371 ofInternational PCT Application No. PCT/US2017/063901,filed Nov. 30, 2017,which claims the benefit of priority to U.S. Provisional PatentApplication No. 62/428,427, titled “Implant Cutting Block PinPlacement,” filed on Nov. 30, 2016, each of which is incorporated hereinby reference in its entirety.

TECHNICAL FIELD

The present disclosure relates generally to apparatus, methods, andsystems for computer-aided orthopedic surgery. More specifically, thepresent disclosure relates to using computer-aided drilling devicealignment to control cutting block pin-hole placement to make implantsurgery more efficient.

BACKGROUND

The use of computers, robotics, and imaging to aid orthopedic surgery iswell known in the art. There has been a great deal of study anddevelopment of computer-aided navigation and robotic systems used toguide surgical procedures. For example, a precision freehand sculptor(PFS) employs a robotic surgery system to assist the surgeon inaccurately cutting a bone into a desired shape. In procedures such astotal hip replacement, computer-aided surgery techniques have been usedto improve the accuracy, reliability of the surgery. Orthopedic surgeryguided by images has also been found useful in preplanning and guidingthe correct anatomical position of displaced bone fragments infractures, allowing a good fixation by osteosynthesis.

Cut guides or cutting blocks can be used in an orthopedic surgery toassist a surgeon in cutting or modifying some portions of a target bone.For example, in joint replacement surgeries such as total hipreplacement (THR) or total knee replacement (TKR), the preparation ofthe bones can involve pinning/screwing saw guide cutting blocks to thebones, so that a reciprocating saw blade can be held steady along itsintended path. Placement of these blocks can be guided by manualinstrumentation or through the use of jigs.

The positioning of cutting blocks can be a time consuming andcomplicated process, which is critical to positive outcomes for thepatient. Mechanisms that allow the cutting blocks to be adjusted withinthe required workspace are complex, and require high machiningtolerances, adding to costs and complexity of these instrument systems.

Manual alignment, in particular, can be cumbersome and is limited toinformation obtainable through mechanical and visual referencing means.The instruments used to manually align cutting blocks cannot fullycapture the 3D shape of the bones, nor can they adequately captureinformation about kinematics of the joint or soft tissue tension orlaxity. Such instruments are expensive to create and to manage. Suchinstruments require significant operational and cleaning costs. Thesecosts increase the burden of managing cutting blocks. Mechanicalreferencing instruments can add to the burden of managing cut guides orcutting blocks.

SUMMARY

There is provided a system for drilling holes in a target bone. Thesystem includes a cutting tool, a navigation system configured to tracka position of the cutting tool, and a computer-assisted surgical (CAS)system operably connected to the cutting tool and the navigation system.The CAS system configured to determine an implant component to beimplanted on the target bone, determine a cutting block position forpreparing the target bone to receive the implant component, determine aplurality of pin locations for securing a cutting block to the targetbone based upon the determined cutting block position, and selectivelyprovide instructions to the cutting tool to cut a hole when the cuttingtool is in a position adjacent to at least one of the determinedplurality of pin locations.

In some embodiments, the navigation system may be configured to trackthe position information for the cutting tool and transmit the positioninformation to the CAS system. In some additional embodiments, the CASsystem may be further configured to receive the position informationfrom the navigation system, determine a location and orientation of thecutting tool based upon the received position information, and providethe instructions to cut at least a portion of the hole when thedetermined location of the cutting tool is adjacent to at least one ofthe determined plurality of pin locations.

In some embodiments, the CAS system may be further configured todetermine implant configuration information, wherein the implantconfiguration information comprises at least one of hole trajectoryinformation, implant sizing information, labelling information, planarcut positioning information, planar cut orientation information, andassociated cutting block information. In some additional embodiments,the CAS system may be further configured to select the cutting block,wherein the cutting block comprises a size and shape, determine holelocation information for the selected cutting block based upon theimplant configuration information and the cutting block size and shape,and determine the plurality of pin locations based upon the determinedhole location information.

In some embodiments, the CAS system may be further configured to receivea surgical plan that defines an implant procedure for the target boneand determine the implant component based upon the received surgicalplan. In some additional embodiments, the surgical plan may define aknee replacement procedure.

In some embodiments, the cutting tool is a computer-controlled cuttingtool.

In some embodiments, the cutting tool is a handheld cutting tool.

In some embodiments, the cutting block includes an opening configured toconstrain a sawblade.

There is also provided a device for assisting in drilling holes in atarget bone. The device includes a processing device operably connectedto a computer readable medium configured to store one or moreinstructions. When executed, the instructions cause the processingdevice to determine an implant component to be implanted on the targetbone, determine a cutting block position for preparing the target boneto receive the implant component, determine a plurality of pin locationsfor securing a cutting block to the target bone based upon thedetermined cutting block position; and selectively provide instructionsto a cutting tool operably connected to the processing device to cut ahole when the cutting tool is in a position adjacent to at least one ofthe determined plurality of pin locations.

In some embodiments, the one or more instructions may include additionalinstructions that, when executed, cause the processing device to receiveposition information for the cutting tool, determine a location andorientation of the cutting tool based upon the received positioninformation, and provide the instructions to cut at least a portion ofthe hole when the determined location of the cutting tool is adjacent toat least one of the determined plurality of pin locations.

In some embodiments, the one or more instructions may include additionalinstructions that, when executed, cause the processing device todetermine implant configuration information, wherein the implantconfiguration information comprises at least one of hole trajectoryinformation, implant sizing information, labelling information, planarcut positioning information, planar cut orientation information, andassociated cutting block information. In some additional embodiments,the one or more instructions may include additional instructions that,when executed, cause the processing device to: select the cutting block,wherein the cutting block comprises a size and shape; determine holelocation information for the selected cutting block based upon theimplant configuration information and the cutting block size and shape;and determine the plurality of pin locations based upon the determinedhole location information.

In some embodiments, the one or more instructions may include additionalinstructions that, when executed, cause the processing device to receivea surgical plan that defines an implant procedure for the target bone,and determine the implant component based upon the received surgicalplan. In some additional embodiments, the surgical plan may define aknee replacement procedure.

The example embodiments as described above can provide variousadvantages over prior techniques. For example, the techniques as taughtherein can reduce the time spent finding the optimal position for acutting block for a specific implant component. The techniques alsoprovide for more accurately locating the implant component in theoptimal position by utilizing a robotically-assisted surgical system todrill holes in a precise location for pinning the cutting block in theoptimal position for a specific implant component.

Further features and advantages of at least some of the embodiments ofthe present disclosure, as well as the structure and operation ofvarious embodiments of the present disclosure, are described in detailbelow with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and form a part ofthe specification, illustrate the embodiments of the invention andtogether with the written description serve to explain the principles,characteristics, and features of the invention. In the drawings:

FIG. 1 illustrates an example of an implant that can be attached to abone as part of a surgical procedure in accordance with certainembodiments of the present disclosure.

FIG. 2A is a block diagram depicting a system for providing surgicalnavigation to ensure an orthopedic procedure is consistent with asurgical plan in accordance with certain embodiments of the presentdisclosure.

FIG. 2B is an illustration of an operating room with a system employinga cutting tool in accordance with certain embodiments of the presentdisclosure.

FIG. 2C is a perspective view of a hand-held cutting device with a cutguard in accordance with certain embodiments of the present disclosure.

FIG. 3 is a block diagram depicting a system for tracking a drillingdevice to place one or more pin holes for an implant cutting block pinor pins in accordance with certain embodiments of the presentdisclosure.

FIG. 4A is a perspective view of a knee joint showing a femur, a tibia,and a pair of pin holes in accordance with certain embodiments of thepresent disclosure.

FIG. 4B is a perspective view of a knee joint showing a femur, a tibia,and a pair of pins that have been placed in the pin holes shown in FIG.4A in accordance with certain embodiments of the present disclosure.

FIG. 4C is a perspective view of a knee joint showing a femur, a tibia,a pair of pins, and a cutting block in accordance with certainembodiments of the present disclosure.

FIG. 5 is a flow diagram showing a sample process for positioning acutting block in accordance with certain embodiments of the presentdisclosure.

DETAILED DESCRIPTION

This disclosure is not limited to the particular systems, devices andmethods described, as these may vary. The terminology used in thedescription is for the purpose of describing the particular versions orembodiments only, and is not intended to limit the scope.

As used in this document, the singular forms “a,” “an,” and “the”include plural references unless the context clearly dictates otherwise.Unless defined otherwise, all technical and scientific terms used hereinhave the same meanings as commonly understood by one of ordinary skillin the art. Nothing in this disclosure is to be construed as anadmission that the embodiments described in this disclosure are notentitled to antedate such disclosure by virtue of prior invention. Asused in this document, the term “comprising” means “including, but notlimited to.”

The embodiments of the present teachings described below are notintended to be exhaustive or to limit the teachings to the precise formsdisclosed in the following detailed description. Rather, the embodimentsare chosen and described so that others skilled in the art mayappreciate and understand the principles and practices of the presentteachings.

This disclosure describes example systems and methods of implementing anavigation system to control a drilling device to drill pilot holes in abone to prepare the bone for attachment to an implant. In the followingdescription, for purposes of explanation, numerous specific details areset forth in order to provide a thorough understanding of exampleembodiments. It will be evident to one skilled in the art, however, thatembodiments can be practiced without these specific details.

For the purposes of this specification, the term “implant” is used torefer to a prosthetic device or structure manufactured to replace orenhance a biological structure. For example, in a knee replacementprocedure, an implant can be placed on one or both of the tibia andfemur. While the term “implant” is generally considered to denote aman-made structure (as contrasted with a transplant), for the purposesof this specification, an implant can include a biological tissue ormaterial transplanted to replace or enhance a biological structure.

The disclosed navigation system can track a drilling device to determineupdated position information for the drilling device. As used herein,position information can include some combination of positioninformation, orientation information, alignment information, and otherrelated spatial information that can be used to determine the currentposition of the drilling device. The position information can be used toalign and/or guide the drilling device to drill the pilot holes inpredetermined positions. The system ensures proper placement of a cutguide or cutting block on the bone without the use of jigs or othersimilar devices that are used to locate the pilot holes in manualprocedures or conventional computer-assisted implant surgery. The cutguide or cutting block can be utilized to ensure that the bone, asshaped by the cutting tool, can receive the implant.

The navigation system can be configured to implement a hand-heldrobotically-assisted tool called the NAVIO®. NAVIO is a registeredtrademark of BLUE BELT TECHNOLOGIES, INC. of Pittsburgh, Pa. Thenavigation system can facilitate the implementation of cutting toolsthrough the NAVIO®. These cutting tools can be tracked to control thecutting action of the cutting element based on its position relative tothe bone and the surgical plan.

The navigation system can correlate a planned implant location relativeto the bone with a database that contains the necessary pin trajectoriesassociated with each cutting block. The system can utilize the surgicalplan and coordinate transforms to define where the cut block designaligns with the necessary cuts for the implant. The system can determinewhere the pin trajectories lie within in the cut block, which can beused to determine the proper placement of the pilot holes without theneed for manual alignment. The system can precisely align the cuttingblock without the need to utilize a jig that is placed with trackers orcouplers to eliminate an unnecessary step in conventional robot-assistedimplant surgical procedures.

The disclosed navigation system utilizes direct guidance to drill/millthe pin holes. Then, the cutting blocks are mounted directly on the boneusing a pin. This avoids many of the drawbacks associated with theexisting methods of robotic-assisted total knee arthroplasty (TKA) inwhich a robotic hand-piece that includes bur/mill fixation features isused to position the cutting blocks on the bone surface.

It should be noted that, as used herein, using a pin to secure or mount,for example, a cutting block includes using any type of medical fastenersuch as a pin, post, threaded screw, self-tapping screw, or othersimilar fastener for mounting the cutting block to a target bone oranother similar surface. Similarly, a hole drilled into a target bonecan be sized to accommodate some portion of the pin. For example, thehole may be shallowly drilled into the bone for receiving a smallportion (e.g., 10% of the length) of the pin for location purposes.Additionally, the hole may be drilled deeply into the bone (e.g., 90% ofthe length) of the pin for both location and orientation/alignmentpurposes. In some examples, the depth of the hole may be about 2 cm. Inother examples, the depth of the hole may range from about 1.0 cm toabout 3.0 cm. In other examples, the depth of the hole may range fromabout 0.25 cm to about 5.0 cm.

Unlike conventional surgical navigation systems which utilizepreoperative imaging, the disclosed navigation system uses imagelessregistration and planning to drill holes to precisely mount a cuttingblock to further shape the bone with more efficient instruments (i.e.saws). This feature distinguishes the disclosed navigation system fromsurgical navigation systems that are used for pedicle screw placement.In such systems, the pedicle screws are the implants.

FIG. 1 illustrates an exemplary implant 100 that can be used in kneereplacement surgery. In certain embodiments, the exemplary implant 100is placed at the distal end of the patient's femur. The implant 100 maybe attached to a surface formed from a bone cut on a post-operative bone(not shown). The implant 100 may include an interfacing surface sizedand shaped to be in close contact with the post-operative surfaces ofthe target bone. The interfacing surface may include multiple facets110A-D oriented in conformity with the cutting planes 110A-D,respectively.

When a surgeon places the implant 100 in a joint, the surgeon must oftencreate holes or channels in the bone that mirror protrusions on theimplant 100 that keep it affixed to the bone in the proper position. Foroptimal fit, the surgeon can use a cutting tool, such as a spinning buror a saw, to shape the bones to receive corresponding implants with aslittle gap as possible. Certain embodiments of the invention utilize asagittal reciprocating saw.

FIGS. 2A-2C illustrate components of a surgical navigation system 200for controlling cutting elements during a procedure through virtualplacement of an implant, according to certain embodiments. The surgicalnavigation system 200 may assist a surgeon in cutting or modifying someportions of a target bone. For example, in joint replacement surgeriessuch as total knee replacement, the surgical navigation system 200 maybe used to align and/or to guide the surgeon to selectively cut portionsof the ends of the target bones and replace those portions withendoprosthetic implants, such as the implant 100 shown in FIG. 1.

FIG. 2A illustrates a block diagram for the surgical navigation system200, which includes a computer system 210 to provide a display forviewing location data provided by optical trackers 212 as read by aninfrared camera system 214. The optical trackers 212 and infrared camerasystem 214 may provide data relevant to the precise location of thebones in the knee joint. In certain embodiments, the infrared camerasystem 214 may detect tracking spheres located on the optical trackers212 in order to gather location data regarding the patient's femur andtibia on which a procedure is to be performed.

FIG. 2B illustrates an exemplary optical surgical navigation setup. Theinfrared camera 216 and optical trackers 220 may be used to performsurgical navigation as discussed. The optical trackers 220 may berigidly attached to any object (such as the surgical tool 226) that thesurgeon wishes to track during the procedure. The camera 216 maycontinuously monitor the workspace during the procedure and the trackers220 are detected from those images. Using the known rigid spatialrelationship of the trackers 220 to a surgical tool, the position of acutting element 224 on the tool 222 in a three-dimensional space may betracked and continuously output to the display 218. The display 218 mayalso continuously display the cutting element 224 location relative tothe patient's anatomy.

FIG. 2C illustrates a hand-held cutting tool 228 that may be used inconjunction with certain embodiments of the present invention. Aspreviously disclosed in U.S. Pat. No. 6,757,582 to Brisson et at., theentirety of which is incorporated herein as if more fully set forth, thetool 228 is tracked by a camera (such as camera 216 in FIG. 2B) thatoptically detects the trackers 220 and communicates that information toa computer system that is also tracking the bones within the surgicalspace and comparing the location of the tool 228 with a pre-determinedsurgical plan. In certain embodiments, the tool 228 turns on when thecutting element 230 is in a position where the surgical plan indicatesthe bone should be cut and then turns off when the tool 228 is near bonethat is to be preserved. In certain other embodiments, the cuttingelement 230 is caused to extend and cut in places where it is supposedto cut and retracts behind the cut guard 232 when it is not supposed tocut the bone. In still further embodiments, the cutting element 230 maybe extended a controlled distance away from the guard so that it onlycuts to a certain depth or at a certain distance away from the distalend 234 of the guard in accordance with the surgical plan.

FIG. 3 is a block diagram of an exemplary surgical navigation system 300that may be configured and implemented to have the functionality toposition a cutting element to create pin holes that will properly placecut guides or cutting blocks (not shown) in an appropriate position thatis consistent with a pre-determined surgical plan. The surgicalnavigation system 300 may utilize more information than traditionalsystems that utilize manually-placed mechanical jigs. The informationmay include range of motion capture, and intraoperatively orpreoperatively defined anatomic landmarks.

The cut guide or cutting block can be attached to the bone to ensurethat the cutting tool shapes the bone correctly. The cutting block canbe attached to a bone with pins. The cut guide or cutting blocks ensurethat the surgeon does not remove too much bone, which may result in animplant that does not fit properly, is loose, or may be subject toimplant dislocation or failure.

The surgical navigation system 300 may configure and implement atracking device 310 that is connected to a surgical plan generationsystem 320 and a drilling device 330. The surgical navigation system 300may be configured and implemented as a single system for the alignmentof multiple types of jigs to support multiple surgeries and implantdesigns. It is to be appreciated that embodiments of the describedsubject matter may be implemented by various types of operatingenvironments, computer networks, platforms, frameworks, computerarchitectures, and/or computing devices.

The tracking device 310 may align and/or control the drilling device 330to drill pin holes in a bone in accordance with a surgical plan that isgenerated by the surgical plan generation system 320. The pin holes arealigned for proper placement of a cut guide or cutting block (not shown)on the bone by the navigation system 300 and the tracking device 310. Incertain embodiments, the drilling device 330 may be controlled by arobot that is programmed to drill the pin holes. In certain otherembodiments, the drill may be tracked by the navigation system andmanually operated by a member of the surgical team.

The tracking device 310 and/or the surgical plan generation system 320may include one or more processors and memory devices, as well asvarious input devices, output devices, communication interfaces, and/orother types of devices. The tracking device 310 and/or the surgical plangeneration system 320 may include a combination of hardware andsoftware.

The tracking device 310 and/or the surgical plan generation system 320may implement and utilize one or more program modules or similar sets ofinstructions contained in a computer readable medium or memory (e.g.,memory 350) for causing a processing device (e.g., processor 340) toperform one or more operations. Generally, program modules includeroutines, programs, objects, components, data structures, etc., thatperform particular tasks or implement particular abstract data types.

The tracking device 310 and/or the surgical plan generation system 320may be implemented by one or more computing devices such as computers,PCs, server computers configured to provide various types of servicesand/or data stores in accordance with aspects of the described subjectmatter. Exemplary server computers may include, without limitation: webservers, front end servers, application servers, database servers,domain controllers, domain name servers, directory servers, and/or othersuitable computers. Components of tracking device 310 and/or surgicalplan generation system 320 may be implemented by software, hardware,firmware or a combination thereof.

The tracking device 310 may include the processor 340, memory 350, inputdevices 360, drilling device interface 370, implant database 380, andcutting block database 390. The input devices 360 may be configured andimplemented to receive a surgical plan from the surgical plan generationsystem 320 for attaching an implant to a bone. The surgical plan mayutilize a cutting block to guide a cutting tool to remove a portion ofthe bone to facilitate accurate placement of the implant. The surgicalplan may be utilized by the processor 340, immediately, or may be storedin memory 350 for later use. It should be understood that the trackingdevice 310 may configure and implement a single database that may bepartitioned into the implant database 380 and the cutting block database390.

The tracking device 310 may configure and implement the processor 340 toaccess the implant database 380 to identify the implant (or implants)that are the subject of the surgical plan. The processor 340 may obtainimplant geometry for the implant(s) from the implant database 380. Theprocessor 340 may determine the implant location relative to the bonefrom the surgical plan.

The tracking device 310 may configure and implement the processor 340 toaccess the cutting block database 390. The processor 340 may utilize thecutting block database 390 to determine the cutting block positionrelative to the implant location for the surgical plan. The processor340 may obtain at least one cutting tool trajectory from the cuttingblock database 390.

Once the processor 340 obtains the above-described information for theimplant and the cutting block, the processor 340 may determine on ormore pin locations (usually a pair) for attaching the cutting block tothe bone. The processor 340 may utilize the relationship between theimplant location, the cutting block position, and the cutting tooltrajectory to determine the pin locations.

The tracking device 310 may configure and implement the drilling deviceinterface 370 to track the drilling device 330 to position the drillingdevice 330 over one of the pin locations. The drilling device 330 maydrill a hole at the pin location. Then, the drilling device interface370 may align the drilling device 330 to position the drilling device330 over a second pin location. The drilling device 330 may drill a holeat the second pin location.

The drilling device 330 may include any type of tracked tool, robotichand-piece, or autonomous robot that facilitates the ability to drillholes according to the necessary position and orientation guided orgoverned by the tracking device 310. It should be also noted that thedrilling device 330 is described herein by way of example only. Incertain implementations, additional cutting tools can be used to createthe holes at the pin locations. For example, a saw including a moving orreciprocating saw blade can be used to create the holes and the pinlocations.

The implant database 380 may include information for each implant and/orimplant design family (e.g. Journey II, Legion, Genesis), includinginformation for each size component. The information may include the 3Dshape of the implant (e.g. STL data), mounting implant peg holetrajectories (defined in the coordinate space of the 3D shape data),metadata describing sizing and labelling information, and geometryinformation describing the position and orientation of planar cuts to bemade with a saw in order to install the implant. Each implant in theimplant database 380 may be correlated with one or more compatible cutguide or cutting block.

The cutting block database 390 includes information relating one or morecut guide or cutting block to compatible implants in the implantdatabase 380. The cutting block database 390 may physically define sawcut trajectories relative to a particular cut guide or cutting block.The cut guide or cutting blocks may be pinned to the bone to hold themrigidly to the bone during the cut. The cutting block database 390 mayinclude information relating to pin holes for a particular cut guide orcutting block.

The cutting block database 390 may contain trajectory and placement datarelating to the pin holes for each cut guide or cutting block. Thecutting block database 390 may contain coordinate transform information(either explicitly, through specification in the cutting block database390, or implicitly through assumed common coordinate definitions). Thecoordinate transforms may describe an expected alignment for the cutguide or cutting block, as well as implant coordinate systems. Theimplant coordinate systems may indicate how cut trajectories maycoincide with the necessary planar cuts for installation of the implant.

The tracking device 310 may configure and implement the processor 340 tocorrelate a planned implant location relative to the bone utilizing theinformation contained in the implant database 380 and the cutting blockdatabase 390. The processor 340 may utilize surgical navigationprinciples to determine the proper pin placement when three variablesare known. The variables include the location of the implant (relativeto the tracker), the proper placement of the cut guide (or cuttingblock) to align the expected cuts with the implant shape, and thelocation of the pins are for a particular cut guide (or cutting block).

The processor 340 may utilize the surgical plan and the coordinatetransforms to determine a necessary pin placement through the equation:trackerTpin=trackerTimplant*implantTcutblock*cutblockTpinwhere trackerTpin represents at least one of the pin locations,trackerTimplant represents the position of the implant on the bone,implantTcutblock represents the position of the cutting block on thebone, and cutblockTpin represents the cutting tool trajectory.

The processor 340 may utilize other surgical navigation principles andcoordinate transforms. For example, the processor 340 may utilizecoordinate transforms for implants that include parallel facets thatallow for sliding along a common direction (e.g., for a total kneeimplant, mediolaterally). Such transforms include a degree of freedomthat gives flexibility to a cut guide or cutting block that may berelative to a planned location for an implant. In such transforms, theImplantTcutblock variable may be initialized to a nominal position, suchthat the processor 340 may allow for further manipulation along thisdegree of freedom.

FIGS. 4A-4C illustrate an example of a knee joint 400 that is beingprepared for shaping by a cutting tool 410 to form one or more surfacesfor receiving an implant, such as implant 100 shown in FIG. 1. The kneejoint 400 includes a femur 412 and a tibia 414. A cutting block 416 ispositioned on the tibia 414 to ensure that the cutting tool 410 makesthe proper cut on the tibia 414 without removing an excess amount ofbone material. The cutting block 416 may be aligned on the tibia 414without having to use manual instrumentation sets, so that the cuttingblock 416 may be smaller and less intricate than conventional cutguides, cutting blocks, and/or jigs.

The cutting block 416 includes a channel or slot 418 to guide thecutting tool 410. The slot 418 constrains the cutting tool 410 toeliminate vibration and errant cuts during cutting operations. Forexample, the slot 418 can be configured to restrain a saw blade of thecutting tool 410. In this exemplary embodiment, the slot 418 should beparallel to a bone removal line on the tibia 414.

FIG. 4A illustrates the femur 412 in an essentially vertical alignmentwith the tibia 414. The tibia 414 includes a pair of pin holes 420 and422 that have been produced with a drilling device, such as the drillingdevice 330, shown in FIG. 3. In this exemplary embodiment, the positionsof the pin holes 420 and 422 have been determined by the processor 340using information contained within the implant database 380 and thecutting block database 390. The tracking device 310 utilized thedrilling device interface 370 to make sure that the drilling device 330positioned the pin holes 420 and 422 in the proper positions.

FIG. 4B illustrates the femur 412 tilted at a slight angle with respectto the tibia 414. A first pin 424 has been inserted into pin hole 420. Asecond pin 426 has been inserted into pin hole 422. The pins 424 and 426are oriented in a manner to support the cutting block 416 on the tibia414 in an orientation that will allow the tibia 414 to be shaped tosupport an implant, such as the implant 110 shown in FIG. 1.

FIG. 4C illustrates the cutting block 416 being attached to the tibia414. The tibia 414 is abuts the femur 412 with the femur 412 beingaligned essentially perpendicularly to the tibia 414. The cutting block416 includes a pair of pin holes 428 and 430 for receiving the pins 424and 426.

It should be noted that attaching a cutting block to a tibia as shown inFIGS. 4A-4C is provided by way of example only. In certainimplementations, the processes and techniques as described herein can beused to prepare holes in additional bones for mounting of a cuttingblock thereon. For example, holes may be prepared in a femur forattachment of a cutting block to prepare the femur to receive a femoralimplant component. Similarly, holes may be prepared in a vertebra forreceiving a cutting block for preparing at least a portion of apatient's spine for receiving an interbody spinal implant.

FIG. 5 illustrates a sample process for using a computer-assistedsurgical (CAS) system, such as the surgical systems described above, fordrilling hole in a target bone for mounting, for example, a cuttingblock. The CAS system may receive 505 a surgical plan including, forexample, information related to the surgical procedure such as surgerytype (e.g., total knee replacement, partial knee replacement), implantfamily, implant size, optimal implant location, and other relatedinformation. Based upon the surgical plan, the CAS system may determine510 the implant component that is to be used during the procedure. Insome examples, the CAS system may determine 510 the implant component byextracting this information from the surgical plan. In other examples,the CAS system may determine 510 the implant component based upon aselection of the implant component by, for example, a surgeon performingthe procedure. In some examples, the CAS system may optionally determine512 implant component geometry based upon the determine 510 implantcomponent. For example, as noted above, the CAS system may access adatabase or other similar data store to determine 512 the implantcomponent geometry.

The CAS system may also determine 515 the implant location for thepatient. In some examples, the surgeon may use a display device or othersimilar device operably connected to the CAS system to change orotherwise adjust the location of the implant. Based upon the implantposition, the CAS system may determine 520 the cutting block location.In some implementations, determining 520 the cutting block location mayinclude selecting the cutting block to use and determining the size andshape of the cutting block.

The CAS system may also determine 525 the pin locations for the cuttingblock based upon the cutting block location and, based upon the pinlocations, the pin hole locations on the target bone. In someimplementations, determining 525 the pin and hole locations may be basedupon the size and shape of the cutting block. For example, dependingupon the size of cutting block, the CAS system may determine two orthree pin and hole locations. For example, the cutting block may includetwo surface pins for mounting the cutting block to a target bone, and athird hole positioned such that a third pin is placed at an angle to thefirst two pins, thereby locking the cutting block into position on thebone. In such an example, the CAS system may determine three pin andassociated pin hole locations.

The CAS system may also track 530 the drilling device using, forexample, location information received from a navigation system asdescribed above. For example, the navigation system may be configured torecord and transmit position information related to the current positionof the cutting tool to the CAS system. The CAS system can receive thisinformation, and determine location and orientation information for thecutting tool based upon the position information. Depending upon thecurrent position of the cutting device, the CAS system may operate 535the drilling device by selectively providing operation instruction tothe cutting device. For example, the CAS system determines that thedrilling device is in a position adjacent to one of the pin holelocations, the CAS system may provide instructions for the cutting toolto align with the hole location and drill at least a portion of thehole. In certain implementations, the drilling device may include adrill bit, or other cutting device, that includes an adjustablealignment for fine aiming of the drilled hole. In such an example, theCAS system can provide instructions for the drilling device to align thedrill bit with the hole to be drilled and drill the whole asappropriate.

It should be noted that the process as shown in FIG. 5 is provided byway of example only. In certain implementation, the process steps shown,and the order performed, can be altered accordingly. For example, theCAS system may be configured to continually track 530 the drillingdevice throughout the surgical procedure, and not merely limited totracking the surgical device as shown in the process order of FIG. 5 anddescribed in the above discussion,

In some implementations, there is also provided a method for drillingholes in a target bone. The method includes receiving an indication ofan implant component to be implanted on the target bone, determining acutting block position for preparing the target bone to receive theimplant component, determining a plurality of pin locations for securinga cutting block to the target bone based upon the determined cuttingblock position, and selectively providing instructions to a cutting tooloperably connected to the processing device to cut a hole when thecutting tool is in a position adjacent to at least one of the determinedplurality of pin locations.

In some embodiments, providing instructions to the cutting tool mayinclude receiving position information for the cutting tool, determininga location and orientation of the cutting tool based upon the receivedposition and orientation information, and providing the instructions tocut at least a portion of the hole when the determined location of thecutting tool is adjacent to at least one of the determined plurality ofpin locations.

In some embodiments, the method may include determining implantconfiguration information, wherein the implant configuration informationcomprises at least one of hole trajectory information, implant sizinginformation, labelling information, planar cut positioning information,planar cut orientation information, and associated cutting blockinformation.

In some additional embodiments, determining the cutting block positionmay include: selecting the cutting block, wherein the cutting blockcomprises a size and shape; determining hole location information forthe cutting block based upon the implant configuration information andthe cutting block size and shape; and determining, by the processingdevice, the plurality of pin locations based upon the determined holelocation information.

In some embodiments, receiving an indication of the implant componentmay include receiving a surgical plan that defines an implant procedurefor the target bone and selecting the implant component based upon thereceived surgical plan.

In some additional embodiments, the surgical plan may define a kneereplacement procedure.

In the above detailed description, reference is made to the accompanyingdrawings, which form a part hereof. In the drawings, similar symbolstypically identify similar components, unless context dictatesotherwise. The illustrative embodiments described in the detaileddescription, drawings, and claims are not meant to be limiting. Otherembodiments may be used, and other changes may be made, withoutdeparting from the spirit or scope of the subject matter presentedherein. It will be readily understood that various features of thepresent disclosure, as generally described herein, and illustrated inthe Figures, can be arranged, substituted, combined, separated, anddesigned in a wide variety of different configurations, all of which areexplicitly contemplated herein.

The present disclosure is not to be limited in terms of the particularembodiments described in this application, which are intended asillustrations of various features. Many modifications and variations canbe made without departing from its spirit and scope, as will be apparentto those skilled in the art. Functionally equivalent methods andapparatuses within the scope of the disclosure, in addition to thoseenumerated herein, will be apparent to those skilled in the art from theforegoing descriptions. Such modifications and variations are intendedto fall within the scope of the appended claims. The present disclosureis to be limited only by the terms of the appended claims, along withthe full scope of equivalents to which such claims are entitled. It isto be understood that this disclosure is not limited to particularmethods, reagents, compounds, compositions or biological systems, whichcan, of course, vary. It is also to be understood that the terminologyused herein is for the purpose of describing particular embodimentsonly, and is not intended to be limiting.

With respect to the use of substantially any plural and/or singularterms herein, those having skill in the art can translate from theplural to the singular and/or from the singular to the plural as isappropriate to the context and/or application. The varioussingular/plural permutations may be expressly set forth herein for sakeof clarity.

It will be understood by those within the art that, in general, termsused herein, and especially in the appended claims (for example, bodiesof the appended claims) are generally intended as “open” terms (forexample, the term “including” should be interpreted as “including butnot limited to,” the term “having” should be interpreted as “having atleast,” the term “includes” should be interpreted as “includes but isnot limited to,” et cetera). While various compositions, methods, anddevices are described in terms of “comprising” various components orsteps (interpreted as meaning “including, but not limited to”), thecompositions, methods, and devices can also “consist essentially of” or“consist of” the various components and steps, and such terminologyshould be interpreted as defining essentially closed-member groups. Itwill be further understood by those within the art that if a specificnumber of an introduced claim recitation is intended, such an intentwill be explicitly recited in the claim, and in the absence of suchrecitation no such intent is present.

For example, as an aid to understanding, the following appended claimsmay contain usage of the introductory phrases “at least one” and “one ormore” to introduce claim recitations. However, the use of such phrasesshould not be construed to imply that the introduction of a claimrecitation by the indefinite articles “a” or “an” limits any particularclaim containing such introduced claim recitation to embodimentscontaining only one such recitation, even when the same claim includesthe introductory phrases “one or more” or “at least one” and indefinitearticles such as “a” or “an” (for example, “a” and/or “an” should beinterpreted to mean “at least one” or “one or more”); the same holdstrue for the use of definite articles used to introduce claimrecitations.

In addition, even if a specific number of an introduced claim recitationis explicitly recited, those skilled in the art will recognize that suchrecitation should be interpreted to mean at least the recited number(for example, the bare recitation of “two recitations,” without othermodifiers, means at least two recitations, or two or more recitations).Furthermore, in those instances where a convention analogous to “atleast one of A, B, and C, et cetera” is used, in general such aconstruction is intended in the sense one having skill in the art wouldunderstand the convention (for example, “a system having at least one ofA, B, and C” would include but not be limited to systems that have Aalone, B alone, C alone, A and B together, A and C together, B and Ctogether, and/or A, B, and C together, et cetera). In those instanceswhere a convention analogous to “at least one of A, B, or C, et cetera”is used, in general such a construction is intended in the sense onehaving skill in the art would understand the convention (for example, “asystem having at least one of A, B, or C” would include but not belimited to systems that have A alone, B alone, C alone, A and Btogether, A and C together, B and C together, and/or A, B, and Ctogether, et cetera). It will be further understood by those within theart that virtually any disjunctive word and/or phrase presenting two ormore alternative terms, whether in the description, claims, or drawings,should be understood to contemplate the possibilities of including oneof the terms, either of the terms, or both terms. For example, thephrase “A or B” will be understood to include the possibilities of “A”or “B” or “A and B.”

In addition, where features of the disclosure are described in terms ofMarkush groups, those skilled in the art will recognize that thedisclosure is also thereby described in terms of any individual memberor subgroup of members of the Markush group.

As will be understood by one skilled in the art, for any and allpurposes, such as in terms of providing a written description, allranges disclosed herein also encompass any and all possible subrangesand combinations of subranges thereof. Any listed range can be easilyrecognized as sufficiently describing and enabling the same range beingbroken down into at least equal halves, thirds, quarters, fifths,tenths, et cetera. As a non-limiting example, each range discussedherein can be readily broken down into a lower third, middle third andupper third, et cetera. As will also be understood by one skilled in theart all language such as “up to,” “at least,” and the like include thenumber recited and refer to ranges that can be subsequently broken downinto subranges as discussed above. Finally, as will be understood by oneskilled in the art, a range includes each individual member. Thus, forexample, a group having 1-3 cells refers to groups having 1, 2, or 3cells. Similarly, a group having 1-5 cells refers to groups having 1, 2,3, 4, or 5 cells, and so forth.

Various of the above-disclosed and other features and functions, oralternatives thereof, may be combined into many other different systemsor applications. Various presently unforeseen or unanticipatedalternatives, modifications, variations or improvements therein may besubsequently made by those skilled in the art, each of which is alsointended to be encompassed by the disclosed embodiments.

What is claimed is:
 1. A system for controlling a surgical tool withrespect to a target bone, the system comprising: a computer-assistedsurgical (CAS) system configured to: determine an implant component tobe implanted on the target bone, determine a first cutting planecorresponding to the implant component, wherein the first cutting planedefines a pose of a planar cut to remove a portion of the target bone toprepare the target bone to receive the implant, determine a cuttingblock corresponding to the implant component, determine a second cuttingplane corresponding to the cutting block, wherein the second cuttingplane defines a pose of a plane cut by the surgical tool when receivedby the cutting block, determine a cutting block position for the cuttingblock by aligning the first cutting plane and the second cutting plane,determine a tool trajectory for a surgical tool according to thedetermined cutting block position, and control the surgical toolaccording to the determined tool trajectory to cause the surgical toolto prepare the target bone for placement of the cutting block.
 2. Thesystem of claim 1, wherein the CAS system is configured to: track theposition information for the cutting block with respect to the targetbone.
 3. The system of claim 1, wherein the CAS system is furtherconfigured to: receive a surgical plan that defines an implant procedurefor the target bone; and determine the implant component based upon thereceived surgical plan.
 4. The system of claim 3, wherein the surgicalplan defines a knee replacement procedure.
 5. The system of claim 1,wherein the cutting block comprises an opening configured to constrain asawblade.
 6. The system of claim 1, wherein the surgical tool comprisesa drill.
 7. A device for controlling a surgical tool with respect to atarget bone, the device comprising: a processing device operablyconnected to a computer readable medium configured to store one or moreinstructions that, when executed, cause the processing device to:determine an implant component to be implanted on the target bone,determine a first cutting plane corresponding to the implant component,wherein the first cutting plane defines a pose of a planar cut to removea portion of the target bone to prepare the target bone to receive theimplant, determine a cutting block corresponding to the implantcomponent, determine a second cutting plane corresponding to the cuttingblock, wherein the second cutting plane defines a pose of a plane cut bythe surgical tool when received by the cutting block, determine acutting block position for the cutting block by aligning the firstcutting plane and the second cutting plane, determine a tool trajectoryfor a surgical tool according to the determined cutting block position,and control the surgical tool according to the determined tooltrajectory to cause the surgical tool to prepare the target bone forplacement of the cutting block.
 8. The device of claim 7, wherein theone or more instructions comprise additional instructions that, whenexecuted, cause the processing device to: receive position informationfor the cutting block; and determine a location and orientation of thecutting block based upon the received position information.
 9. Thedevice of claim 7, wherein the one or more instructions compriseadditional instructions that, when executed, cause the processing deviceto: receive a surgical plan that defines an implant procedure for thetarget bone; and determine the implant component based upon the receivedsurgical plan.
 10. The device of claim 9, wherein the surgical plandefines a knee replacement procedure.
 11. The device of claim 7, whereinthe surgical tool comprises a drill.